The Past Comes to Meet the Future!

 I suppose every living creature tends to perceive the world in terms of its own species. So when we humans look at history, we look back at all the events down through the ages of human habitation on earth, including what we now describe as the development of civilization. It seems like such a very long time ago when our species was in its early stages. Humans have changed and evolved so much in a few thousand years that it takes an effort for us to even recognize our early ancestors as relatives.

In contrast, I've been engrossed in a PBS series about the evolution of our planet in which the time dimensions are mind-blowing. The episode I just finished is about Pangea, the supercontinent that included almost all the land on the planet. Pangea existed here 299 million years ago, and it lasted for 26 million years. Compare those numbers to our human historical ones! Scientists have been able to read Pangea's history from messages in rock fossils and formations, so we know what kinds of plants and animals lived here then. In its prime, Pangea had a lush ecosystem with trees and plants and animals. And then everything died. Scientists from all over the world working in association with each other now have a better understanding of what happened when this great extinction hit. Until recently, we knew that this almost complete die-off of life had something to do with erupting volcanoes in the north. This went on for thousands of years and not only covered much land in lava, but also poisoned the atmosphere with toxic chemicals. Yet because this was happening only in the north, there was still a mystery about how it affected the whole planet. The most recent theory is that when the lava from those northern volcanoes cooled, it was so thick that it finally created a cap through which no more lava could flow. Instead, the hot lava began circulating underground around the globe, and when it hit coal or salt deposits, it caught them on fire. At some point, the underground fires got so fierce that they exploded out of the ground, carrying the toxic air that had formed with the coal and salt molecules. The upshot was that not only were there pervasive ground fires, but the air became full of carbon dioxide. Almost nothing could survive. 

"Almost" is an important word here. We have had a number of extinctions on earth, and each time some tiny fragment of life was able to find a way to survive. In the Pangea extinction, some might have gone underground to avoid the heat, others might have been able to survive on the changed composition of the air. So each time there has been an extinction on earth, some tiny part of life has survived. And each time life evolved again to fill our planet, each time with different life forms. The planet has continued. And life has always found a way to go on, to recover and ultimately to thrive.....at least until the next extinction.

Why is this history important to us today? Because we're almost certainly heading for another extinction. The evolution of the earth is measured in thousands and millions of years, so usually things take awhile to develop. The proportion of carbon dioxide in the air has been an important contributor to extinctions. One sobering fact is that compared to the volcanoes and lava flow at the end of Pangea, our modern industrial culture is putting carbon dioxide into the air at a much faster rate. Climate change is happening much more quickly than we predicted a few years ago. Even though there are still folks who deny that the climate is changing or that we have anything to do with it, the evidence clearly points to a world that is getting warmer and an atmosphere that has less oxygen and more carbon dioxide. So what do we do? How do we think about this? Tough questions.

At the end of the Pangea PBS episode, one scientist pointed out that human beings are an incredible species. We are creative and ingenious. We've put a man on the moon, for Pete's sake! Surely we can figure out how to mend this problem. But as we all know, first we have to want to do something about it. If we had not gotten entranced by material wealth and controlling the environment (if we could have remained in touch with the natural world like many indigenous peoples), it would be easier to make the changes we need to make and slow the speed of climate change. In our present political climate, it is hard to be optimistic. Yet there are many of us who work for a healthier planet. And my grandchildren's generation gives me hope, for they see things in a fresher and more open way. As for me, my approach is two-fold. I do what I can to speak out for earthcare in its many forms, and I use these days of my life to explore the miraculous life forms around me, with wonder and gratitude.

Sometimes I pretend I am some life form on a distant planet, and I look down on the earth. It's an amazing place with such an incredible history. Once again its life is in peril, and it looks like this time it is because of the effect of human civilization on the biosphere. Yet I'm not filled with blame or retribution. We are all in this together, and we are all imperfect. Greed, anger, dominance, prejudice...., they are all part of the human condition. And we do our best with what we're given. If eventually this epoch of humanity dies out, we have at least had a very good run. And the earth will eventually recover with some new spread of evolving species. Wouldn't it be fun to be a fly on the wall (or tree?) in a million years and see what has happened?